Sole‐Solvent High‐Entropy Electrolyte Realizes Wide‐Temperature and High‐Voltage Practical Anode‐Free Sodium Pouch Cells

Advanced Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 21, 2025

Abstract Anode‐free sodium batteries (AFSBs) hold great promise for high‐density energy storage. However, high‐voltage AFSBs, especially those can stably cycle at a wide temperature range are challenging due to the poor electrolyte compatibility toward both cathode and anode. Herein, AFSBs with cycling ability in (−20–60 °C) realized first time via sole‐solvent high‐entropy based on diethylene glycol dibutyl ether solvent (D2) NaPF 6 salt. The unique solvent‐ions effect of strong anion interaction weak cation solvation enables entropy‐driven salt disassociation high‐concentration contact ion pairs, thus simultaneously forming stable anion‐derived electrode–electrolyte interphases Moreover, liquid D2 further extends extremes battery. Consequently, ampere‐hour (Ah)‐level anode‐free pouch cells cyclability −20–60 °C realized. Impressively, cell achieves leadingly high cell‐level density 209 Wh kg −1 capacity retention 83.1% after 100 cycles 25 °C. This work provides inspirations designing advanced electrolytes practical AFSBs.

Language: Английский

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Rate‐Dependent Failure Behavior Regulation of LiFePO₄ Cathode via Functional Interface Engineering

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 23, 2025

Abstract LiFePO 4 is extensively used as a cathode material in lithium‐ion batteries because of its high safety profile, affordability, and extended cycle life. Nevertheless, inherently low transport kinetics restricted electronic conductivity considerably limit rate performance. Furthermore, the failure mechanisms specific to various cycling rates are not well examined. This study presents functional interface layer designed regulate rate‐dependent behavior . At elevated charge/discharge rates, this facilitates mobility, decreases internal polarization, alleviates mechanical stress, reduces structural degradation. lower it contributes formation stable cathode‐electrolyte interphase (CEI), effectively suppressing side reactions minimizing active lithium loss. Consequently, modified demonstrates enhanced stability capacity retention, with retention after 400 cycles at 2C increasing from 76.5% 98.6% 5C 40.2% 90.0%. Through combinations experimental data theoretical analysis, elucidates key underlying rate‐specific regulation, providing valuable insights into relationship between ion dynamics stability. approach represents an effective strategy for supporting potential use advanced energy storage systems that require both rapid charging prolonged

Language: Английский

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Solvation chemistry in liquid electrolytes for rechargeable lithium batteries at low temperatures

EcoEnergy, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 12, 2025

Abstract Over the past few decades, significant advancements have been made in development of low‐temperature liquid electrolytes for lithium batteries (LBs). Ongoing exploration is crucial further enhancing performance these batteries. Solvation chemistry plays a dominant role determining properties electrolyte, significantly affecting LBs at low temperatures (LTs). This review introduces solvation structures and their impact, discussing how promote fast desolvation processes contribute to improvement battery performance. Additionally, various solvent strategies are highlighted refine LTs, including use linear cyclic ethers/esters, as well functional groups within solvents. The also summarizes impact salts containing organic/inorganic anions on chemistry. Characterization techniques discussed, providing comprehensive analysis that offers valuable insights developing next‐generation ensure reliable across wide temperature range.

Language: Английский

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The future of carbon anodes for lithium-ion batteries: The rational regulation of graphite interphase

Carbon Future, Journal Year: 2024, Volume and Issue: unknown, P. 9200017 - 9200017

Published: Aug. 1, 2024

Language: Английский

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Trace NaBF₄ Modulated Ultralow‐Concentration Ether Electrolyte for Durable High‐Voltage Sodium‐Ion Batteries

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 13, 2025

Abstract Ultralow‐concentration ether electrolytes hold great promise for cost‐effective sodium‐ion batteries (SIBs), while their inferior cycle stability under high voltages remains an awkward challenge. Herein, ultralow‐concentration diglyme (G2)‐based with single sodium salt are found to manifest high‐rate capability when employed high‐voltage Na 3 (VOPO 4 ) 2 F (NVOPF) cathode, but specific capacity rapidly depletes exhaustion during long‐term cycling. To address this issue, trace NaBF (0.03 m as electrolyte additive is introduced, which minimally affects ion conductivity of the pristine electrolyte, yet weakens coordination between + ions and G2 molecules. This allows more PF 6 − enter solvation sheath ions, forming a stable cathode interphase enhancing performance without sacrificing (up 20 C). As result, modulated G2‐based enables NVOPF steadily, retention 94.2% over 1000 cycles at low rate 1 C. work provides valuable insights into modulation use in durable SIBs.

Language: Английский

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Compensating K Ions Through an Organic Salt in Electrolytes for Practical K‐Ion Batteries

Angewandte Chemie International Edition, Journal Year: 2025, Volume and Issue: unknown

Published: March 7, 2025

Abstract K‐ion batteries face significant challenges due to a severe shortage of active K ions, with cathode materials typically containing less than 70% ions and first‐cycle irreversible reactions consuming up 20% more. Conventional compensation methods fail supply sufficient without compromising cell integrity. To address this, we introduce potassium sulfocyanate (KSCN) as an electrolyte additive capable delivering 100% ions. During initial charging, KSCN undergoes oxidative decomposition at 3.6 V, releasing forming the cosolvent thiocyanogen ((SCN) 2 ). This molecule, meeting diverse electrochemical properties, was identified using unsupervised machine learning cheminformatics. The approach demonstrated full conversion excellent compatibility all components. presence (SCN) enhanced rate capability anodes by promoting desolvation. In hard carbon|K 0.5 Mg 0.15 [Mn 0.8 0.05 ]O pouch cell, this tripled capacity through supplying 58% showcasing practical solution for in batteries.

Language: Английский

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Combined Effect of Fluoride Enables the Stable Charging–Discharging Cycle of Carbonate-Based Li-Ion Pouch Cells at −30 °C

ACS Materials Letters, Journal Year: 2025, Volume and Issue: unknown

Published: March 12, 2025

Language: Английский

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Compensating K Ions Through an Organic Salt in Electrolytes for Practical K‐Ion Batteries

Angewandte Chemie, Journal Year: 2025, Volume and Issue: unknown

Published: March 7, 2025

Abstract K‐ion batteries face significant challenges due to a severe shortage of active K ions, with cathode materials typically containing less than 70% ions and first‐cycle irreversible reactions consuming up 20% more. Conventional compensation methods fail supply sufficient without compromising cell integrity. To address this, we introduce potassium sulfocyanate (KSCN) as an electrolyte additive capable delivering 100% ions. During initial charging, KSCN undergoes oxidative decomposition at 3.6 V, releasing forming the cosolvent thiocyanogen ((SCN) 2 ). This molecule, meeting diverse electrochemical properties, was identified using unsupervised machine learning cheminformatics. The approach demonstrated full conversion excellent compatibility all components. presence (SCN) enhanced rate capability anodes by promoting desolvation. In hard carbon|K 0.5 Mg 0.15 [Mn 0.8 0.05 ]O pouch cell, this tripled capacity through supplying 58% showcasing practical solution for in batteries.

Language: Английский

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Dynamic doping and interphase stabilization for cobalt-free and high-voltage Lithium metal batteries

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: March 21, 2025

Cobalt-free spinel LiNi0.5Mn1.5O4 (LNMO) positive electrodes, promise high energy density when coupled with lithium negative due to the discharge voltage platform. However, intrinsic dissolution of Mn in electrode, electrolyte decomposition at voltage, and dendrite growth on severely compromise cycling stability, limiting practical application. Herein, we propose ferrocene hexafluorophosphate as an additive achieve dynamic doping Fe3+ electrodes during electrochemical cycling. Furthermore, molecule preferentially decomposes both electrode interfaces, forming thin, dense inorganic interphase F, P-rich solid respectively, effectively stabilizing interfaces. Consequently, Li | |LNMO batteries based modified electrolytes enhance stability rate performance a charge cutoff 4.9 V LNMO pouch cell performs consistently over 160 cycles. Additionally, efficacy extends beyond LNMO, demonstrating its universal applicability operating challenging voltages, including LiNi0.8Co0.1Mn0.1O2, LiNi0.6Co0.2Mn0.2O2, LiCoO2 470 Wh kg−1 level metal was successfully realized. Mn-based suffer from serious problems. Here, authors stabilization electrodes.

Language: Английский

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A Strong Interfacial Adhesion and High Stress Dissipation Binder for Durable Microsized SiO_x Anodes

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: April 24, 2025

Abstract The rapid capacity decay of microsized SiO x anode resulting from large volume change hinders its commercial application. Herein, a polymer binder with strong interfacial adhesion and high stress dissipation is designed to alleviate the maintain structural integrity electrode. density functional theory calculations (DFT) X‐ray photoelectron spectroscopy (XPS) reveal that multifunctional polymeric network enhances contact between silicon oxide (SiO ) particles through gradient hydrogen bonds. Additionally, exhibits mechanical strength self‐healing function via synergy supramolecular covalent chemistry. enables electrodes exhibit notable cycling stability superior rate performances. This work provides valuable insights into structure‐function relationship for high‐capacity anodes.

Language: Английский

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